Bernie Gunther, a cop who solves homicides in a Nazi Germany of wholesale murder, investigates a mass grave in Katyn Forest, rumored to hold the bodies of officers held as POWs and then massacred by the Russians.

In “A Man Without Breath,” Philip Kerr’s latest book featuring Gunther, it is 1943. Hitler’s army has been defeated at Stalingrad, and Germans holding the Russian town of Smolensk, near Katyn Forest, are bracing for a Russian onslaught.

Goebbels, the minister of propaganda for the Third Reich, sees the chance to vilify the Russians in the international press and panic German soldiers into fighting to the death against such a merciless enemy. He instructs Gunther to oversee the forensic unearthing of the bodies under the watchful eye of the Red Cross and journalists.

But Gunther is more interested in who killed two men assigned to man the Smolensk telephone exchange by cutting their throats as they returned from a local brothel. The killings are conveniently blamed on Russian partisans, but Gunther knows the evidence points to a killer who is a fellow German. More murders follow.

“A Man Without Breath” focuses on an enclave of wealthy Prussian aristocrats who despise the Nazis and want only to wrest control back from Hitler. But Kerr conveys the whole broad swath of the particular time, plunging the reader into a densely realized history replete with mosquitoes and the stench of bodies, castles and cathedrals, Franco’s Spain and anti-Polish prejudice, military hierarchies and Walther guns.

Always surefooted, reeling off names with aplomb, Kerr spins out a dozen plotlines and some moments of keen suspense and sadness. In the process, he takes his flawed hero up to and even over some perilously thin moral edges.